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Definitely spoiled by SpaceX's polish. I'm not sure how much of the displayed telemetry was right, as the altitude of Stage 2 was shown as decreasing down and down until suddenly they said it was in orbit. The imperial units don't help understanding either.

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It's normal for altitude to decrease while the second stage builds up to orbital velocity; the Shuttle did the same thing.

Like all rockets, the second stage has a thrust/weight ratio substantially lower than 1 on ignition, and the motor points far away from the gravity vector, so there's a bit of a race between the vehicle trying to fall down, and the rocket motor trying to accelerate it to orbital velocity. The fact that the final orbit was 100 miles exactly suggests this all went according to plan.

IIRC when I played KSP it was necessary to point slightly down if you wanted to reach orbit in a continuous burn, rather than waiting to burn more at perigee. Is that true in general?

(was playing with a mod that models ullage, so relighting was quite finicky)

There's a great Eager Space youtube video about it: https://www.youtube.com/watch?v=XxEy9mDeq40

Imperial units helped me

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